PARM-DATA in hex looks as, this is also same for every value I am passing thru the PARM

Code:

00003E00
00010100

My skepticalism would be yelling at me at this point.
My solution would to put a unique display (compile date?...'hello, this is test 1A', anything...) into the display to insure I was seeing the execution of the program I thought I was executing....

I really can't help you there, but, as I've learned, when the impossible is happening, you have (obviously) missed something...
Sometimes plugging a unique phrase or date/time into a display will prove or disprove that you are actually executing the program you think (are sure) you are actually executing....
Been there, done that, 'got the T-Shirt'....sometimes the simplest errors can 'cloud' the thinking....

Hopefully, your system has standard compile jcl procs. Some for CICS, some for batch, some for database, etc and combinations. It is a very dangerous practice for each developer to have their own and not use common procs. . .

Might it be that the batch job was simply compiled with other than the standard batch compile jcl?